Barrett's esophagus (BE), defined as the development of intestinal metaplasia in the esophagus, is a premalignant condition that predisposes to adenocarcinoma of the esophagus. The incidence of adenocarcinoma of the gastric cardia and esophagus is increasing more rapidly than any other cancer. The factors responsible for the development of Barrett's esophagus, and the transformation from Barrett's to cancer are largely unknown. In order to prevent the development of cancer, clinicians perform regular endoscopic examinations to discover dysplastic changes that might signal higher risk for cancer. The appropriate surveillance interval is not known. The objective of this application is to seek funds to develop a protocol for a multi-center randomized trial of two different surveillance intervals of patients with Barrett's esophagus. The investigators are members of a clinical trials consortium that has conducted clinical trials for the past decade. The study will test the hypothesis that the currently recommended 2-year surveillance interval can safely be extended to 4 years. The planning grant would provide a mechanism to refine disease definitions, outcome measures, sample size, and analysis plans and to address feasibility issues. A detailed protocol will be developed as part of the planning process. A companion case control study of risk factors for Barrett's will provide new insight into the development and perhaps the prevention of this disease.